WO2022095719A1 - 航空发动机压气机及其可调静子叶片位置保持结构 - Google Patents

航空发动机压气机及其可调静子叶片位置保持结构 Download PDF

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Publication number
WO2022095719A1
WO2022095719A1 PCT/CN2021/125464 CN2021125464W WO2022095719A1 WO 2022095719 A1 WO2022095719 A1 WO 2022095719A1 CN 2021125464 W CN2021125464 W CN 2021125464W WO 2022095719 A1 WO2022095719 A1 WO 2022095719A1
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WO
WIPO (PCT)
Prior art keywords
adjustable stator
aero
stator blade
engine compressor
section
Prior art date
Application number
PCT/CN2021/125464
Other languages
English (en)
French (fr)
Inventor
王家广
朱彬
张苗苗
高豪迈
曹传军
Original Assignee
中国航发上海商用航空发动机制造有限责任公司
中国航发商用航空发动机有限责任公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 中国航发上海商用航空发动机制造有限责任公司, 中国航发商用航空发动机有限责任公司 filed Critical 中国航发上海商用航空发动机制造有限责任公司
Priority to CA3200857A priority Critical patent/CA3200857A1/en
Priority to US18/251,755 priority patent/US12044133B2/en
Priority to EP21888416.1A priority patent/EP4242468A4/en
Publication of WO2022095719A1 publication Critical patent/WO2022095719A1/zh

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/52—Casings; Connections of working fluid for axial pumps
    • F04D29/54—Fluid-guiding means, e.g. diffusers
    • F04D29/56—Fluid-guiding means, e.g. diffusers adjustable
    • F04D29/563—Fluid-guiding means, e.g. diffusers adjustable specially adapted for elastic fluid pumps
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/52—Casings; Connections of working fluid for axial pumps
    • F04D29/54—Fluid-guiding means, e.g. diffusers
    • F04D29/541—Specially adapted for elastic fluid pumps
    • F04D29/542—Bladed diffusers
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D17/00—Regulating or controlling by varying flow
    • F01D17/10—Final actuators
    • F01D17/12—Final actuators arranged in stator parts
    • F01D17/14—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits
    • F01D17/16—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits by means of nozzle vanes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
    • F01D—NON-POSITIVE DISPLACEMENT MACHINES OR ENGINES, e.g. STEAM TURBINES
    • F01D17/00—Regulating or controlling by varying flow
    • F01D17/10—Final actuators
    • F01D17/12—Final actuators arranged in stator parts
    • F01D17/14—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits
    • F01D17/16—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits by means of nozzle vanes
    • F01D17/162—Final actuators arranged in stator parts varying effective cross-sectional area of nozzles or guide conduits by means of nozzle vanes for axial flow, i.e. the vanes turning around axes which are essentially perpendicular to the rotor centre line
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04D—NON-POSITIVE-DISPLACEMENT PUMPS
    • F04D29/00—Details, component parts, or accessories
    • F04D29/40—Casings; Connections of working fluid
    • F04D29/52—Casings; Connections of working fluid for axial pumps
    • F04D29/54—Fluid-guiding means, e.g. diffusers
    • F04D29/541—Specially adapted for elastic fluid pumps
    • F04D29/542—Bladed diffusers
    • F04D29/544—Blade shapes
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2220/00—Application
    • F05D2220/30—Application in turbines
    • F05D2220/32—Application in turbines in gas turbines
    • F05D2220/323—Application in turbines in gas turbines for aircraft propulsion, e.g. jet engines
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2240/00—Components
    • F05D2240/10—Stators
    • F05D2240/12—Fluid guiding means, e.g. vanes
    • F05D2240/128—Nozzles
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00—Function
    • F05D2260/30—Retaining components in desired mutual position
    • F05D2260/37—Retaining components in desired mutual position by a press fit connection
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05D—INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS
    • F05D2260/00—Function
    • F05D2260/60—Fluid transfer

Definitions

  • the invention relates to the field of aviation technology, in particular to an aero-engine compressor and its adjustable stator blade position maintaining structure.
  • stator blades In order to improve the margin of the high-pressure compressor in all working conditions, the first few stages of stator blades are usually designed as adjustable stator blades, and the adjustable stator blades are adjusted according to the working conditions during the working process. Install the angle to ensure that the high-pressure compressor has sufficient margin, thereby ensuring the safe operation of the whole machine.
  • the outer journal of the adjustable stator blade is installed in the stator blade journal mounting hole of the stator casing.
  • a non-metallic blade is usually arranged between the blade and the blade mounting hole of the casing.
  • the easy-to-wear bushings are usually fitted with small clearances between the blade journal and the bushing and between the bushing and the blade mounting holes on the stator casing.
  • the adjustable stator blade will be inclined under the action of the airflow during the working process, and the axis of the blade journal deviates from the design expectation, so that the blade position deviates from the design expectation, and the effect of rectifying the airflow becomes poor;
  • One object of the present invention is to provide an adjustable stator blade position maintaining structure for an aero-engine compressor, which can solve the problems existing in the prior art and keep the adjustable stator blades at the Predetermined position, thereby improving the aerodynamic performance of the high-pressure compressor to a certain extent.
  • an adjustable stator blade position maintaining structure for an aero-engine compressor
  • the adjustable stator blade position maintaining structure includes a positioning section, a limiting section and a force transmission section
  • the The positioning section is installed in the mounting hole on the casing
  • the limiting section is in the shape of a cone to match with the conical hole on the top of the journal of the adjustable stator blade
  • the force transmission section is connected to the positioning section and the limiting segment, so as to transmit the load from the limiting segment to the positioning segment.
  • the position maintaining structure of the adjustable stator blade for the aero-engine compressor of the present invention can achieve the following beneficial technical effects: when the aero-engine compressor is working, the adjustable stator blade is kept in a predetermined position, and then the adjustable stator blade is kept at a certain position. Improve the aerodynamic performance of the high-pressure compressor to a certain extent.
  • the present invention proposes an adjustable stator blade position maintaining structure for an aero-engine compressor.
  • the adjustable stator blade position maintaining structure is fixed on the casing and passes through a similar top hole on the outer journal of the adjustable stator blade.
  • the feature of (tapered hole) limits the adjustable stator blade, and the cone of the limiting section cooperates with the tapered hole on the top of the journal of the adjustable stator blade to provide a reaction force when the adjustable stator blade has a tendency to tilt.
  • Achieving the limit of the adjustable stator vanes can prevent the adjustable stator vanes from swaying and deviating from the design position due to the action of the airflow during operation, and improve the realization of the installation angle of the blades in the same stage, thereby improving the aerodynamic performance of the high-pressure compressor to a certain extent. .
  • the positioning section is in the shape of a bushing and is in an interference fit with the mounting hole.
  • the adjustable stator blade position maintaining structure for aero-engine compressors of the present invention can achieve the following beneficial technical effects: the positioning section and then the adjustable stator blade position maintaining structure can be precisely positioned on the casing. in the mounting hole.
  • the cone angle of the limiting section ranges from 45 degrees to 135 degrees.
  • the position maintaining structure of the adjustable stator blades for aero-engine compressors of the present invention can achieve the following beneficial technical effects: by setting the cone angle of the limiting section appropriately, the position of the adjustable stator blades is further enhanced. maintain ability.
  • the linear expansion coefficient of the material of the adjustable stator blade position maintaining structure is greater than or equal to the linear expansion coefficient of the material of the casing or the adjustable stator blade.
  • the adjustable stator blade position maintaining structure for the aero-engine compressor of the present invention can play the following beneficial technical effects: ensure that the positioning surface does not disengage when the aero-engine compressor is actually working.
  • the force transmission section is open.
  • the adjustable stator blade position maintaining structure for aero-engine compressors of the present invention can achieve the following beneficial technical effects: the movement of the rocker arm is not hindered.
  • the opening angle of the force transmission section is the maximum movement angle of the rocker arm for adjusting the installation angle of the adjustable stator blade plus a predetermined margin.
  • the adjustable stator blade position maintaining structure for aero-engine compressors of the present invention can achieve the following beneficial technical effects: more effectively does not hinder the movement of the rocker arm.
  • the ratio of the height of the force transmission section to the height of the limiting section ranges from 3 to 8.
  • the adjustable stator blade position maintaining structure for an aero-engine compressor of the present invention can achieve the following beneficial technical effects: the limiting effect of the limiting section can be better, and the aero-engine compressor can be operated more efficiently.
  • the adjustable stator vanes are effectively maintained in a predetermined position, thereby improving the aerodynamic performance of the high-pressure compressor to a certain extent.
  • the position maintaining structure of the adjustable stator blades works when the aero-engine compressor is in operation, so as to maintain the adjustable stator blades in a predetermined position.
  • the position maintaining structure of the adjustable stator blade for the aero-engine compressor of the present invention can achieve the following beneficial technical effects: it can avoid the deflection and deviation of the adjustable stator blade due to the air flow during the operation of the aero-engine compressor. Design position, thereby improving the aerodynamic performance of the high-pressure compressor to a certain extent.
  • an aero-engine compressor wherein the aero-engine compressor includes the adjustable stator blade position maintaining structure for an aero-engine compressor as described in any one of the preceding aspects.
  • the aero-engine compressor of the present invention can achieve the following beneficial technical effects: when the aero-engine compressor is working, the adjustable stator blades are kept in a predetermined position, thereby improving the aerodynamic performance of the high-pressure compressor to a certain extent.
  • the aero-engine compressor further includes a bushing installed between the journal of the adjustable stator blade and the positioning section.
  • the aero-engine compressor of the present invention can achieve the following beneficial technical effects: the wear between the adjustable stator blades and the position maintaining structure of the adjustable stator blades can be effectively avoided.
  • FIG. 1 is a partial schematic cross-sectional view of an aero-engine compressor according to an embodiment of the present invention.
  • FIG. 2 is a schematic cross-sectional view of an adjustable stator blade position maintaining structure for an aero-engine compressor according to an embodiment of the present invention.
  • adjustable stator vane position maintaining structure refers to a structure for maintaining the position of the adjustable stator vanes.
  • FIG. 1 is a partial schematic cross-sectional view of an aero-engine compressor according to an embodiment of the present invention.
  • 2 is a schematic cross-sectional view of an adjustable stator blade position maintaining structure for an aero-engine compressor according to an embodiment of the present invention. It should be noted that, in order to better show the positional relationship between the adjustable stator vane position maintaining structure 2, the adjustable stator vane 3 and the casing 1, FIG. , showing the entire journal of the adjustable stator vane 3 and a small part of the vane body.
  • an adjustable stator blade position maintaining structure 2 for an aero-engine compressor includes a positioning section 5, a limiting section 7 and a force transmission section 6, wherein the positioning section 5
  • the segment 5 is installed in the mounting hole 11 (that is, the hole for installing the journal of the adjustable stator blade) on the casing 1 (that is, the casing of the aero-engine compressor), and the limiting segment 7 is in the shape of a cone,
  • the force transmission section 6 is connected between the positioning section 5 and the limiting section 7 to transfer the load from the limiting section 7 to the positioning section 5. .
  • the position maintaining structure of the adjustable stator blade for the aero-engine compressor of the present invention can achieve the following beneficial technical effects: when the aero-engine compressor is working, the adjustable stator blade is kept in a predetermined position, and then the adjustable stator blade is kept at a certain position. Improve the aerodynamic performance of the high-pressure compressor to a certain extent.
  • the present invention proposes an adjustable stator blade position maintaining structure for an aero-engine compressor.
  • the adjustable stator blade position maintaining structure is fixed on the casing and passes through a similar top hole on the outer journal of the adjustable stator blade.
  • the feature of (tapered hole) limits the adjustable stator blade, and the cone of the limiting section cooperates with the tapered hole on the top of the journal of the adjustable stator blade to provide a reaction force when the adjustable stator blade has a tendency to tilt.
  • Achieving the limit of the adjustable stator vanes can prevent the adjustable stator vanes from swaying and deviating from the design position due to the action of the airflow during operation, and improve the realization of the installation angle of the blades in the same stage, thereby improving the aerodynamic performance of the high-pressure compressor to a certain extent. .
  • the positioning section 5 is in the shape of a bushing, which is in an interference fit with the mounting hole 11 , so that the positioning section and thus the position maintaining structure of the adjustable stator blade can be precisely positioned on the casing. in the mounting hole on the top.
  • the taper angle of the limiting segment 7 ranges from 45 degrees to 135 degrees.
  • the ability to maintain the position of the adjustable stator vane is further enhanced through the appropriate setting of the cone angle of the limiting segment.
  • the taper angle of the limiting section 7 is 60 degrees.
  • the ability to maintain the position of the adjustable stator vanes is further enhanced by the optimal setting of the cone angle of the limiting segment.
  • the linear expansion coefficient of the material of the adjustable stator blade position maintaining structure 2 is greater than or equal to the linear expansion coefficient of the material of the casing 1 or the adjustable stator blade 3 .
  • the material of the adjustable stator blade position maintaining structure 2 is the same as the material of the casing 1 or the adjustable stator blade 3; in other embodiments, the material of the adjustable stator blade position maintaining structure 2 is the same as that of the casing 1 or the materials of the adjustable stator vanes 3 are inconsistent.
  • the linear expansion coefficient of the material of the adjustable stator vane position maintaining structure 2 should be greater than or equal to the linear expansion coefficient of the material of the casing 1 or the adjustable stator vane 3, so as to ensure The positioning surface does not disengage when the aero-engine compressor is actually working.
  • the force transmission section 6 is open. That is to say, the force transmission section 6 is not in a complete cylindrical shape, and from its cross section, the force transmission section 6 is substantially C-shaped, so as not to hinder the movement of the rocker arm 8 .
  • the opening angle of the force transmission section 6 is the maximum movement angle of the rocker arm 8 used to adjust the installation angle of the adjustable stator blades plus a predetermined margin, so as to not hinder the movement of the rocker arm 8 more effectively.
  • the "rocker arm” is an important part of the aero-engine compressor, which is used to adjust the installation angle of the adjustable stator blades. For example, if the maximum movement angle of the rocker arm 8 for adjusting the installation angle of the adjustable stator blade is 80 degrees, and the predetermined margin is 10 degrees, the opening angle of the force transmission section 6 is 90 degrees.
  • the ratio of the height M of the force transmission section 6 to the height N of the limiting section 7 ranges from 3 to 8.
  • the above-mentioned ratio range of the height of the force transmission section and the height of the limit section can make the limit effect of the limit section better, and more effectively keep the adjustable stator blades in the predetermined position when the aero-engine compressor is working, and then to a certain extent Improve the aerodynamic performance of high pressure compressors.
  • the ratio of the height M of the force transmission section 6 to the height N of the limiting section 7 is 5.
  • the above ratio of the height of the force transmission section to the height of the limit section can make the limit effect of the limit section better, and more effectively keep the adjustable stator blades in the predetermined position when the aero-engine compressor is working, thereby improving to a certain extent.
  • the height M of the force transmission section 6 is 25 mm
  • the height N of the limiting section 7 is 5 mm
  • the height L of the positioning section 5 is 10 mm.
  • the above-mentioned height of the force transmission section, the height of the limit section and the height of the positioning section are only a preferred form of the height of each section adopted by the adjustable stator blade position maintaining structure of the aero-engine compressor.
  • Personnel can understand on the basis of the disclosure of the present application that other suitable heights of each segment may also be adopted without departing from the protection scope of the claims of the present application.
  • the adjustable stator vane position maintaining structure 2 works when the aero-engine compressor is working, so as to keep the adjustable stator vanes 3 in a predetermined position, so as to prevent the aero-engine compressor from working
  • the middle adjustable stator blades are swayed by the airflow and deviate from the design position, thereby improving the aerodynamic performance of the high-pressure compressor to a certain extent.
  • the flange of the positioning section 5 is connected to the casing 1 .
  • a sealing washer can be added to this gap to further ensure assembly reliability.
  • the positioning segment 5 , the force transmission segment 6 and the limiting segment 7 may be designed to be of equal thickness, or may be designed to be of variable thickness.
  • the positioning section 5 , the force transmission section 6 and the limiting section 7 can be designed as a whole, or can be designed to be welded in sections, or even different materials are selected for each section.
  • the existence of the adjustable stator blade position maintaining structure 2 may increase the rotational resistance of the adjustable stator blade 3. After the assembly is completed, the rotation of the adjustable stator blade should be tested to ensure the same The rotational flexibility of the blades at each stage is comparable.
  • an aero-engine compressor includes an adjustable stator blade position maintaining structure 2 for an aero-engine compressor.
  • the adjustable stator blade position maintaining structure 2 includes a positioning section 5, a limiting section 7 and a force transmission section 6, wherein the positioning section 5 is installed in the mounting hole 11 on the casing 1, and the limiting section 7 is in the shape of a cone, so as to In cooperation with the tapered hole 12 on the top of the journal of the adjustable stator vane 3 , the force transmission section 6 is connected between the positioning section 5 and the limiting section 7 to transmit the load from the limiting section 7 to the positioning section 5 .
  • the aero-engine compressor of the present invention can achieve the following beneficial technical effects: when the aero-engine compressor is working, the adjustable stator blades are kept in a predetermined position, thereby improving the aerodynamic performance of the high-pressure compressor to a certain extent.
  • the aero-engine compressor further includes a bushing 4 installed between the journal of the adjustable stator blade 3 and the positioning section 5, so that the adjustable stator blade and the adjustable stator blade can be effectively avoided.
  • the stator vanes are positioned to maintain wear between the structures.
  • the radially inner end surface of the positioning section 5 is in contact with the radially outer end surface of the mounting hole 11 on the casing 1 (in FIG. 1 , the downward direction is radially inward). , the upward direction is radially outward), thereby realizing the radial positioning of the positioning segment 5 .
  • the inner diameter of the positioning section 5 and the outer diameter of the bushing 4 adopt a small clearance fit.
  • the radially outer end surface of the positioning segment 5 is in contact with the radially inner end surface of the bushing 4 , thereby realizing the radial positioning of the bushing 4 .

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  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
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  • Structures Of Non-Positive Displacement Pumps (AREA)

Abstract

一种用于航空发动机压气机的可调静子叶片位置保持结构（2），在压气机工作时将可调静子叶片（3）保持在预定位置，进而改善压气机气动性能。可调静子叶片位置保持结构（2）包括定位段（5）、限位段（7）和传力段（6），其中，定位段（5）安装在机匣（1）上的安装孔（11）内，限位段（7）呈锥体形状，以与可调静子叶片（3）的轴颈顶部上的锥形孔（12）配合，传力段（6）连接于定位段（5）和限位段（7）之间，以将来自限位段（7）的载荷传递至定位段（5）。

Description

航空发动机压气机及其可调静子叶片位置保持结构 技术领域
本发明涉及航空技术领域，尤其涉及航空发动机压气机及其可调静子叶片位置保持结构。
背景技术
目前国内外航空发动机压气机中，为了改善高压压气机在全工况的裕度，通常将前几级静子叶片设计为可调静子叶片，可调静子叶片在工作过程中根据工况需要调整叶片安装角，以确保高压压气机具有充足的裕度，进而保证整机的安全运转。可调静子叶片的外轴颈安装在静子机匣的静叶轴颈安装孔中，为避免金属叶片与金属机匣之间的磨损，通常在叶片与机匣的叶片安装孔之间布置非金属的易磨衬套，叶片轴颈与衬套之间以及衬套与静子机匣上的叶片安装孔之间多采用小间隙配合。但是现有技术中存在以下问题：
1)可调静子叶片在工作过程中会在气流作用下产生倾斜，叶片轴颈的轴线偏离设计预期，以致叶片位置偏离了设计预期，整流气流的效果变差；
2)同一级内周向各个叶片与衬套、衬套与机匣上叶片安装孔的实际配合间隙因公差分布必然存在一定差异，这种差异一方面导致同一级内可调静子叶片在气流作用下倾斜程度不同，使得同一级内周向各叶片的整流效果存在差异，另一方面导致各级叶片在旋转时产生不同的阻力，进而使得同一级内各叶片在工作时实现的安装角不同，进而对气动性能产生影响；
3)随着发动机过程时间增长，叶片与衬套、衬套与机匣之间的磨损将带来彼此之间的间隙进一步增大，不可避免地，以上1)、2)所述问题将会进一步加剧。
发明内容
本发明的一个目的在于，提供一种用于航空发动机压气机的可调静子叶片位 置保持结构，其能解决现有技术所存在的问题，在航空发动机压气机工作时将可调静子叶片保持在预定位置，进而在一定程度上改善高压压气机气动性能。
本发明的以上目的通过一种用于航空发动机压气机的可调静子叶片位置保持结构来实现，所述可调静子叶片位置保持结构包括定位段、限位段和传力段，其中，所述定位段安装在机匣上的安装孔内，所述限位段呈锥体形状，以与可调静子叶片的轴颈顶部上的锥形孔配合，所述传力段连接于所述定位段和所述限位段之间，以将来自所述限位段的载荷传递至所述定位段。
根据上述技术方案，本发明的用于航空发动机压气机的可调静子叶片位置保持结构能起到以下有益技术效果：在航空发动机压气机工作时将可调静子叶片保持在预定位置，进而在一定程度上改善高压压气机气动性能。
具体地说，本发明提出了一种用于航空发动机压气机的可调静子叶片位置保持结构，可调静子叶片位置保持结构固定在机匣上并通过可调静子叶片外轴颈上类似顶尖孔(锥形孔)的特征对可调静子叶片进行限位，限位段锥体与可调静子叶片的轴颈顶部上的锥形孔配合，在可调静子叶片有倾斜趋势时提供反作用力以实现可调静子叶片的限位，能够避免工作中可调静子叶片受气流作用发生偏摆、偏离设计位置，改善同一级内叶片的安装角实现情况，进而在一定程度上改善高压压气机气动性能。
较佳的是，所述定位段呈衬套形状，与所述安装孔过盈配合。
根据上述技术方案，本发明的用于航空发动机压气机的可调静子叶片位置保持结构能起到以下有益技术效果：能将定位段进而可调静子叶片位置保持结构精密地定位在机匣上的安装孔内。
较佳的是，所述限位段的锥角范围为45度－135度。
根据上述技术方案，本发明的用于航空发动机压气机的可调静子叶片位置保持结构能起到以下有益技术效果：通过合适的限位段锥角设置，进一步增强了对可调静子叶片的位置保持能力。
较佳的是，所述可调静子叶片位置保持结构的材料的线膨胀系数大于等于所述机匣或所述可调静子叶片的材料的线膨胀系数。
根据上述技术方案，本发明的用于航空发动机压气机的可调静子叶片位置保持结构能起到以下有益技术效果：确保在航空发动机压气机实际工作时定位面不 脱开。
较佳的是，所述传力段呈开口式。
根据上述技术方案，本发明的用于航空发动机压气机的可调静子叶片位置保持结构能起到以下有益技术效果：不阻碍摇臂运动。
较佳的是，所述传力段的开口角度为用于调节可调静子叶片安装角的摇臂的最大运动角度加上预定余量。
根据上述技术方案，本发明的用于航空发动机压气机的可调静子叶片位置保持结构能起到以下有益技术效果：更有效地不阻碍摇臂运动。
较佳的是，所述传力段的高度与所述限位段的高度的比值范围为3－8。
根据上述技术方案，本发明的用于航空发动机压气机的可调静子叶片位置保持结构能起到以下有益技术效果：能使限位段的限位效果较好，在航空发动机压气机工作时更有效地将可调静子叶片保持在预定位置，进而在一定程度上改善高压压气机气动性能。
较佳的是，所述可调静子叶片位置保持结构在所述航空发动机压气机工作时起作用，以将所述可调静子叶片保持在预定位置。
根据上述技术方案，本发明的用于航空发动机压气机的可调静子叶片位置保持结构能起到以下有益技术效果：能避免航空发动机压气机工作中可调静子叶片受气流作用发生偏摆、偏离设计位置，进而在一定程度上改善高压压气机气动性能。
本发明的以上目的还通过一种航空发动机压气机来实现，其中，该航空发动机压气机包括如前述任一方面所述的用于航空发动机压气机的可调静子叶片位置保持结构。
根据上述技术方案，本发明的航空发动机压气机能起到以下有益技术效果：在航空发动机压气机工作时将可调静子叶片保持在预定位置，进而在一定程度上改善高压压气机气动性能。
较佳的是，所述航空发动机压气机还包括安装于所述可调静子叶片的轴颈与所述定位段之间的衬套。
根据上述技术方案，本发明的航空发动机压气机能起到以下有益技术效果：能有效避免可调静子叶片与可调静子叶片位置保持结构之间的磨损。
附图说明
图1是本发明一实施例的航空发动机压气机的一局部示意剖视图。
图2是本发明一实施例的用于航空发动机压气机的可调静子叶片位置保持结构的一示意剖视图。
附图标记列表
1、机匣；
2、可调静子叶片位置保持结构；
3、可调静子叶片；
4、衬套；
5、定位段；
6、传力段；
7、限位段；
8、摇臂；
11、安装孔；
12、锥形孔；
L、定位段的高度；
M、传力段的高度；
N、限位段的高度；
ΔT、间隙。
具体实施方式
以下将描述本发明的具体实施方式，需要指出的是，在这些实施方式的具体描述过程中，为了进行简明扼要的描述，本说明书不可能对实际的实施方式的所有特征均作详尽的描述。应当可以理解的是，在任意一种实施方式的实际实施过程中，正如在任意一个工程项目或者设计项目的过程中，为了实现开发者的具体目标，为了满足系统相关的或者商业相关的限制，常常会做出各种各样的具体决策，而这也会从一种实施方式到另一种实施方式之间发生改变。此外，还可以理 解的是，虽然这种开发过程中所作出的努力可能是复杂并且冗长的，然而对于与本发明公开的内容相关的本领域的普通技术人员而言，在本公开揭露的技术内容的基础上进行的一些设计、制造或者生产等变更只是常规的技术手段，不应当理解为本公开的内容不充分。
除非另作定义，权利要求书和说明书中使用的技术术语或者科学术语应当为本发明所属技术领域内具有一般技能的人士所理解的通常意义。本发明专利申请说明书以及权利要求书中使用的“第一”、“第二”以及类似的词语并不表示任何顺序、数量或者重要性，而只是用来区分不同的组成部分。“一个”或者“一”等类似词语并不表示数量限制，而是表示存在至少一个。“包括”或者“包含”等类似的词语意指出现在“包括”或者“包含”前面的元件或者物件涵盖出现在“包括”或者“包含”后面列举的元件或者物件及其等同元件，并不排除其他元件或者物件。“连接”或者“相连”等类似的词语并非限定于物理的或者机械的连接，也不限于是直接的还是间接的连接。
顾名思义，术语“可调静子叶片位置保持结构”是指：用于保持可调静子叶片的位置的结构。
图1是本发明一实施例的航空发动机压气机的一局部示意剖视图。图2是本发明一实施例的用于航空发动机压气机的可调静子叶片位置保持结构的一示意剖视图。需要注意的是，为了更好地显示可调静子叶片位置保持结构2与可调静子叶片3及机匣1的位置关系，图1仅仅示出了可调静子叶片3的一部分而非全部，即，示出了可调静子叶片3的整个轴颈和一小部分叶片本体部。
如图1—图2所示，根据本发明的一实施例，用于航空发动机压气机的可调静子叶片位置保持结构2包括定位段5、限位段7和传力段6，其中，定位段5安装在机匣1(即，航空发动机压气机的机匣)上的安装孔11(即，用于安装可调静子叶片的轴颈的孔)内，限位段7呈锥体形状，以与可调静子叶片3的轴颈顶部上的锥形孔12配合，传力段6连接于定位段5和限位段7之间，以将来自限位段7的载荷传递至定位段5。
根据上述技术方案，本发明的用于航空发动机压气机的可调静子叶片位置保持结构能起到以下有益技术效果：在航空发动机压气机工作时将可调静子叶片保持在预定位置，进而在一定程度上改善高压压气机气动性能。
具体地说，本发明提出了一种用于航空发动机压气机的可调静子叶片位置保持结构，可调静子叶片位置保持结构固定在机匣上并通过可调静子叶片外轴颈上类似顶尖孔(锥形孔)的特征对可调静子叶片进行限位，限位段锥体与可调静子叶片的轴颈顶部上的锥形孔配合，在可调静子叶片有倾斜趋势时提供反作用力以实现可调静子叶片的限位，能够避免工作中可调静子叶片受气流作用发生偏摆、偏离设计位置，改善同一级内叶片的安装角实现情况，进而在一定程度上改善高压压气机气动性能。
在一些实施例中，如图1—图2所示，定位段5呈衬套形状，与安装孔11过盈配合，从而能将定位段进而可调静子叶片位置保持结构精密地定位在机匣上的安装孔内。
在一些实施例中，如图1—图2所示，限位段7的锥角范围为45度－135度。通过合适的限位段锥角设置，进一步增强了对可调静子叶片的位置保持能力。
在一些实施例中，如图1—图2所示，限位段7的锥角为60度。通过最佳的限位段锥角设置，进一步增强了对可调静子叶片的位置保持能力。
在一些实施例中，可调静子叶片位置保持结构2的材料的线膨胀系数大于等于机匣1或可调静子叶片3的材料的线膨胀系数。在一些实施例中，可调静子叶片位置保持结构2的材料与机匣1或可调静子叶片3的材料一致；在另一些实施例中，可调静子叶片位置保持结构2的材料与机匣1或可调静子叶片3的材料不一致，此时选用的可调静子叶片位置保持结构2的材料的线膨胀系数应当大于等于机匣1或可调静子叶片3的材料的线膨胀系数，从而确保在航空发动机压气机实际工作时定位面不脱开。
在一些实施例中，如图1—图2所示，传力段6呈开口式。也就是说，传力段6不是完整的圆筒形状，从其横截面来看，传力段6呈基本C形，从而不阻碍摇臂8运动。
在一些实施例中，传力段6的开口角度为用于调节可调静子叶片安装角的摇臂8的最大运动角度加上预定余量，从而更有效地不阻碍摇臂8运动。
需要注意的是，“摇臂”是航空发动机压气机的一个重要部件，其用于调节可调静子叶片的安装角。例如，用于调节可调静子叶片安装角的摇臂8的最大运动角度为80度，预定余量为10度，则传力段6的开口角度为90度。
在一些实施例中，传力段6的高度M与限位段7的高度N的比值范围为3－8。传力段高度与限位段高度的上述比值范围能使限位段的限位效果较好，在航空发动机压气机工作时更有效地将可调静子叶片保持在预定位置，进而在一定程度上改善高压压气机气动性能。
在一些实施例中，传力段6的高度M与限位段7的高度N的比值为5。传力段高度与限位段高度的上述比值能使限位段的限位效果更好，在航空发动机压气机工作时更有效地将可调静子叶片保持在预定位置，进而在一定程度上改善高压压气机气动性能。
例如，传力段6的高度M为25mm，限位段7的高度N为5mm，定位段5的高度L为10mm。
当然，上述传力段高度、限位段高度和定位段高度仅仅是本申请用于航空发动机压气机的可调静子叶片位置保持结构所采用的各段高度的一种较佳形式，本领域技术人员在本申请公开内容的基础上可以理解，也可采用其他合适的各段高度，而不脱离本申请权利要求的保护范围。
在一些实施例中，如图1所示，可调静子叶片位置保持结构2在航空发动机压气机工作时起作用，以将可调静子叶片3保持在预定位置，从而能避免航空发动机压气机工作中可调静子叶片受气流作用发生偏摆、偏离设计位置，进而在一定程度上改善高压压气机气动性能。
在一些实施例中，如图1所示，当限位段7的锥体与可调静子叶片3的轴颈顶部上的锥形孔12配合时，定位段5的法兰与机匣1之间可能存在间隙ΔT，应通过尺寸链对此间隙ΔT进行控制，使ΔT≯0.05mm。或者，在此间隙处增加一个密封垫圈进一步保证装配可靠性。
在一些实施例中，如图2所示，定位段5、传力段6和限位段7可以设计成等厚的，也可以设计成变厚度的。定位段5、传力段6和限位段7可以设计为一个整体，也可以设计为分段焊接、甚至为各段选择不同的材料。
在一些实施例中，如图1所示，可调静子叶片位置保持结构2的存在可能使得可调静子叶片3旋转阻力增大，装配完成后应对可调静子叶片转动情况进行测试，尽量保证同级各处叶片转动灵活度相当。
如图1所示，根据本发明的一实施例，航空发动机压气机包括用于航空发动 机压气机的可调静子叶片位置保持结构2。可调静子叶片位置保持结构2包括定位段5、限位段7和传力段6，其中，定位段5安装在机匣1上的安装孔11内，限位段7呈锥体形状，以与可调静子叶片3的轴颈顶部上的锥形孔12配合，传力段6连接于定位段5和限位段7之间，以将来自限位段7的载荷传递至定位段5。
根据上述技术方案，本发明的航空发动机压气机能起到以下有益技术效果：在航空发动机压气机工作时将可调静子叶片保持在预定位置，进而在一定程度上改善高压压气机气动性能。
在一些实施例中，如图1所示，航空发动机压气机还包括安装于可调静子叶片3的轴颈与定位段5之间的衬套4，从而能有效避免可调静子叶片与可调静子叶片位置保持结构之间的磨损。
在一些实施例中，如图1所示，定位段5的径向内端面与机匣1上的安装孔11的径向外端面相贴合(图1中，向下方向为径向向内，向上方向为径向向外)，从而实现定位段5的径向定位。在一些实施例中，如图1所示，定位段5的内径与衬套4的外径采用小间隙配合。在一些实施例中，如图1所示，定位段5的径向外端面与衬套4的径向内端面相贴合，从而实现衬套4的径向定位。
以上对本发明的具体实施方式进行了描述，但本领域技术人员将会理解，上述具体实施方式并不构成对本发明的限制，本领域技术人员可以在以上公开内容的基础上进行多种修改，而不超出本发明的范围。

Claims (10)

  1. 一种用于航空发动机压气机的可调静子叶片位置保持结构，其特征在于，所述可调静子叶片位置保持结构包括定位段、限位段和传力段，其中，所述定位段安装在机匣上的安装孔内，所述限位段呈锥体形状，以与可调静子叶片的轴颈顶部上的锥形孔配合，所述传力段连接于所述定位段和所述限位段之间，以将来自所述限位段的载荷传递至所述定位段。
  2. 如权利要求1所述的用于航空发动机压气机的可调静子叶片位置保持结构，其特征在于，所述定位段呈衬套形状，与所述安装孔过盈配合。
  3. 如权利要求1所述的用于航空发动机压气机的可调静子叶片位置保持结构，其特征在于，所述限位段的锥角范围为45度－135度。
  4. 如权利要求1所述的用于航空发动机压气机的可调静子叶片位置保持结构，其特征在于，所述可调静子叶片位置保持结构的材料的线膨胀系数大于等于所述机匣或所述可调静子叶片的材料的线膨胀系数。
  5. 如权利要求1所述的用于航空发动机压气机的可调静子叶片位置保持结构，其特征在于，所述传力段呈开口式。
  6. 如权利要求5所述的用于航空发动机压气机的可调静子叶片位置保持结构，其特征在于，所述传力段的开口角度为用于调节可调静子叶片安装角的摇臂的最大运动角度加上预定余量。
  7. 如权利要求1所述的用于航空发动机压气机的可调静子叶片位置保持结构，其特征在于，所述传力段的高度与所述限位段的高度的比值范围为3－8。
  8. 如权利要求1所述的用于航空发动机压气机的可调静子叶片位置保持结构， 其特征在于，所述可调静子叶片位置保持结构在所述航空发动机压气机工作时起作用，以将所述可调静子叶片保持在预定位置。
  9. 一种航空发动机压气机，其特征在于，包括如前述权利要求中任一项所述的用于航空发动机压气机的可调静子叶片位置保持结构。
  10. 如权利要求9所述的航空发动机压气机，其特征在于，还包括安装于所述可调静子叶片的轴颈与所述定位段之间的衬套。
PCT/CN2021/125464 2020-11-06 2021-10-22 航空发动机压气机及其可调静子叶片位置保持结构 WO2022095719A1 (zh)

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EP21888416.1A EP4242468A4 (en) 2020-11-06 2021-10-22 AIRCRAFT ENGINE COMPRESSOR AND ADJUSTABLE STATOR BLADE POSITION MAINTAINING STRUCTURE THEREFOR

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US20230407760A1 (en) 2023-12-21
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